1. Field of the Invention
In the patent applications identified above, I disclose metal tamping tools for mounting in ballast tamping apparatus of various design, each of which tools includes a shaft for mounting on the reciprocating mechanism in a specific tamping apparatus and at least one shank having a cross-section of selected shape extending from the shaft, with a tool foot removably pinned to the shank. A blade is provided on the extended end of the tool foot for tamping the ballast responsive to operation of the ballast apparatus.
This invention relates to railroad ballast tamping equipment and more particularly, to metal tamping tools which are designed for use in ballast tamping machines of various design and include a shaft configured to mount in the ballast tamping machine of choice, a shaped shank extending from the shaft, a weld ring or nut fitted on the shank and welded to the shaft and a hollow tool foot seated on the shank and welded to the weld ring. In a first preferred embodiment the tool foot is integrally formed with a tamping blade which is offset from the longitudinal centerline of the tool foot and the tool foot is internally configured to fit a tapered shank. Since the tool foot is welded in position on the shank using a weld ring or nut, it is easily replaced by cutting the weld with a torch when the blade is worn to an undesirable extent. The shaft of the tamping tool is designed to fit the reciprocating mechanisms on such automatic tamping machines as the "Jackson", "Plasser", and "Canron" ballast tamping machines, in non-exclusive particular. Furthermore, in a second preferred embodiment of the invention the blade portion of the tool foot is secured to the tool foot by means of bolts or cap screws. The tamping tools of this invention generally include a tool base or shaft which is adapted to mount in one or more of the respective tamping machines, which shaft is fitted with a rigid, tapered shank of uniform design and configured to receive a weld ring or nut and a tool foot having a tapered receptacle. The tool foot is welded to the weld ring or nut, which weld ring or nut is, in turn, welded to the tool shaft in order to facilitate rapid and convenient replacement of the tool foot by cutting the tool foot from the shank at the weld ring or nut.
2. Description of the Prior Art
Ballast tamping tools for packing and securing ballast against and under rail cross-ties in railroad beds are well known in the art. In recent years such tools have been mounted on reciprocating outriggers attached to rail-mounted tamping machines of various description. The outriggers are positioned over the extending ends of the railroad cross-ties and multiple tamping tools, which are bolted or otherwise attached to the outriggers, project downwardly toward the ballast located around, between and beneath the cross-ties. A blade is typically formed integrally with, or is welded or bolted to the extending end of a tool shaft in each of the tamping tools and multiple blades are sequentially plunged into the ballast at points adjacent the cross-ties to pack the ballast around and under the cross-ties as the tool shafts are reciprocated and laterally articulated by the outrigger mechanism. When the ballast is tightly packed around cross-ties spanned by the machine outriggers, the tamping tools are retracted and the tamping machine apparatus is advanced on the rails to locate the tamping tools over cross-ties spanning unpacked ballast.
One of the problems currently existing in automatic tamping machines used to pack ballast around cross-ties in railroad beds is the lack of facility to quickly replace worn tamping tool blades. In a typical blade installation multiple blades are bolted or otherwise attached by means of the tool shafts to reciprocating outriggers in the tamping machines and the blades and tool feet are usually formed in one piece, such that the entire tamping tool must be replaced when the blade wears to an undesirable extent. An alternative solution to the problem of blade wear is to cut the worn blade from the projecting tamping tool with a cutting torch and weld another blade in its place. However, this operation usually cannot be accomplished with the tamping tool mounted on the tamping machine and the time required to weld the new blade onto the tool shaft may exceed the time of removal of the old tool and reattachment of the new tamping tool to the machine. Other solutions to the problem include bolting the blade to the tool foot and periodically replacing the worn blade with a new one. However, experience has shown that under most circumstances irregular wearing of the tool blade frequently destroys either the heads of the connecting bolts or that portion of the foot or shank which supports the blade, rendering replacement of the blade either difficult or impossible.
Tamping tools of various design for use in track ballast tamping or packing machines are known in the art. Typical of these designs is the tool disclosed in U.S. Pat. No. 2,726,871, dated Dec. 13, 1955, to F. Schnellmann and entitled "Attachment of Picks on Track-Packing Machines". This patent details the attachment of a pick or tamping device on track packing machines, wherein that segment of the pick which is clamped on the machine is smooth and cylindrical in shape and engages a slotted sleeve in the pick arm, the slotted sleeve tightened by multiple screws to effect gripping of the pick at longitudinally separated points. U.S. Pat. No. 3,677,187, dated July 18, 1972, to John K. Stewart discloses a "Reversible Tamping Bar" which includes a pair of elongated tamping tool supports with lateral bores adapted for alignment with a common nose bore to receive a bolt for securing the supports on each side of a nose member. The nose member is provided with four inwardly inclined faces for mating with inclined faces in the supports, such that any tendency of the supports to move upwardly places the bolt in tension. A "Ground Engaging Unit for Ballast Tamping Machines" is disclosed in U.S. Pat. No. 3,826,025, dated July 30, 1974, to William A. Elliott. This device includes an upper shaft for connection to a tamping machine and a lower portion for receiving a replaceable shoe. In one embodiment the shoe is attached to the shaft in a wedge-fit and in another embodiment an adhesive is used to effect the desired connection. Another "Tamping Tool" is disclosed in U.S. Pat. No. 4,068,594, dated Jan. 17, 1978, to James E. Crowell, which tool is characterized by a shank and a detachable blade. In one embodiment of the disclosure a detachable wedge is inserted between the upper portion of the foot member and the shank and in a second embodiment, an arcuate joint is provided between the foot member and the shank. The upper portion of the shank is designed to mate with a reciprocating member in a tamping machine. U.S. Pat. No. 4,167,141, dated Sept. 11, 1979, to Glen H. Haywood details a "Percussive Tool With Replaceable Work Bit". This tool includes a replaceable tamping foot for mounting in a shank by a tapered force fit. A repulsive force is generated between the shank and the tamping foot by means of a grease gun to remove the foot from the shank. German Pat. No. 2,723,551 details a pick shaft designed for mounting in a railroad track compacting machine and provided with a cavity which receives a projecting pin mounted in a tool foot, for removably securing the tool foot on the pick shaft.
It is an object of this invention to provide tamping tools having improved removable and replaceable tool feet and blade segments for use in railroad ballast tamping machines.
Another object of the invention is to provide new and improved metal tamping tools which are designed for mounting in various ballast tamping machines and are each characterized by a shaft configured to mount on a tamping machine of selected design, a unitary, hollow tool foot and offset blade which are designed for maximum strength and efficiency and a shank extending from the shaft and configured to receive both a weld ring or nut and the tool foot, which weld ring or nut is welded to the shaft and to the tool foot.
Still another object of this invention is to provide a tamping tool for use in automatic ballast tamping machines such as the Canron, Plasser and Jackson machines, in non-exclusive particular, which tool includes a shaft configured to mount in the machine, a round, tapered shank formed integrally with the shaft and provided with a weld ring or nut at the upper end, which weld ring or nut is welded to the shaft, a foot member having an internal receptacle shaped to receive the shank and also welded to the weld ring or nut and a unitary, offset blade shaped in the extending end of the foot member.
Still another object of this invention is to provide improved tamping tools for attachment to a ballast tamping apparatus, and more particularly, tamping tools which include a shaft adapted for attachment to a reciprocating outrigger in the tamping apparatus, a shank member having a tapered and extending from the shaft, a weld ring or nut fitted on the shank member and welded to the shaft and an improved tool foot having a receptacle designed to snugly receive the shank member and welded to the weld ring or nut, the tool foot also carrying an offset tamping blade, with a bolt or cap screw securing the tamping blade to the tool foot in order to facilitate easy replacement of the tamping blade and the tool foot as a result of wear in the tamping blade.
Another object of the invention is to provide a new and improved tamping tool for use in automatic ballast tamping machines, which tool is characterized by a shaft provided with a shaped upper end for removable attachment to a ballast tamping machine, a round, tapered shank extending from the shaft, a weld ring slidably fitted on the shank and welded to the shaft and an improved tool foot having a tapered internal cavity in a receiving end and a blade bolted on the opposite end in offset relationship with respect to the longitudinal centerline of the tool foot, the receiving end of which tool foot is seated on the tapered shank and welded to the weld ring, wherein the tamping tool can be selectively unbolted from the tamping machine, the tool foot cut from the weld ring with a torch and then removed from the tamping tool shank and the blade unbolted from the tool foot, as desired.
Yet another object of this invention is to provide a tamping tool which is characterized by exceptional strength and ease of maintenance and includes a shaft having one end configured for attachment to a ballast tamping machine of corresponding design and the opposite end including a round, tapered shank which slidably receives a cooperating weld ring or nut which is welded to the shaft, the shank also designed to receive and mount a hollow tool foot by welding the tool foot to the weld ring or nut. A blade segment is optionally attached to the tool foot by means of bolts or cap screws, welded to the tool foot, or is formed integrally with the tool foot.
Another object of this invention is to provide an improved tamping tool for attachment to a ballast tamping apparatus, which tool includes a base or shaft configured and adapted for attachment to a reciprocating outrigger in the tamping apparatus, a round, shaped shank projecting from the shaft, a weld nut fitted on the shank and welded to the shaft and a foot having a hollow interior also fitted on the shank and welded to the weld nut, the foot carrying a flange fitted with a shaped tamping blade which is offset from the longitudinal centerline of the foot.
A still further object of the invention is to provide a new and improved tamping tool which is characterized by a shaped shank extending from a base or shaft member configured to mount in a ballast tamping machine; a weld ring or nut fitted on the shank and welded to the shaft; a tool foot member having an internal cavity configured to snugly receive the shaped shank and also welded to the weld ring or nut and a blade flange carrying a tamping blade and provided with an opening to threadibly receive a bolt or capscrew and removably retain the tamping blade on the shaped shank.